2.
Key concern
• Climate change could lead to
• More rain over the North Atlantic
• Melting of the Greenland Ice Sheet
• This would lead to a drop in salinity and may slow-
down – or even shut-down – the thermohaline
circulation

7.
Hosing
• Coupled atmosphere-ocean general circulation
models project a slight weakening of the
thermohaline circulation
• The impact of a more drastic weakening are studied
using so-calling hosing experiments, in which a
Death Star suddenly appears to spout freshwater
into the North Atlantic

12.
Wrap-up
• Warming is bad, cooling is worse
• The cooling due to a shut- or slowdown of the
thermohaline circulation is modest relative to the
warming that would induce that.
• Reduced warming would lead to a welfare gain in
most countries